Hi Peoples; - suspect I've found a problem here - I'll explain my actions (Win 7 64-bit)
Due to a necessary re-installation I had an old and damaged version of Windows 7 in the C drive.
When I had extricated all that I required - I dumped it in the Recycle Bin as I then wanted to destroy it using a 35 pass overwrite.
Instead of Opening CCleaner and then running it - I simply clicked on Run CCleaner from the Recycle Bin dropdown menu; - the folders and files totalled some 50G of rubbish - much to my surprise the Recycle Bin emptied immediately! - surely a 35 pass wipe on ~ 50G should take around 15 hours?
So as far as I'm concerned I'm suspicious that the folders etc were NOT thoroughly overwritten!
Please could someone explain what has occured as I do not wish for the trash to be hidden away somewhere in the depths of the hard drive - only to resurface sometime in the future? Thank you.